Device for forming plastic protectors around electrical elements



Sept. 9, 1958 A. F. RUS 2,850,765

DEVICE FOR FORMING PLASTIC PROTECTORS AROUND ELECTRICAL ELEMENTS Filed Aug. 30, 1954 5 Sheets-Sheet 1 v FY/7AM T 70PM? Sept. 9, 1958 Filed Aug. 30, 1954 A. F. RUS 2,850,765 DEVICE FOR FORMING PLASTIC PROTECTORS AROUND ELECTRICAL ELEMENTS 3 Sheets-Sheet 2 Sept. 9, 1958 A. F. RUS 2,850,765

DEVICE FOR FORMING PLASTIC PROTECTORS AROUND ELECTRICAL ELEMENTS 3 Sheets-Sheet 3 I Filed Aug. 30, 1954 3 1 76., 6 /3 W '11 W T U W if I 1 t l I v 4 I a x I I 57 w f4 j;fl

. r I 4 I United States Patent.

DEVICE FOR' FORMING PLASTIC PROTECTORS. AROUND ELECTRICAL ELEMENTS Albert E. Rus, Riverside, Ill., assignor to Western Electric Company, lncorporatedjtNew York,. N. Y;, a corpora-- tion of New York Application August30; 1954', SeriaI'No. 452,974

3'Claims. (Cl; 18'-19) sizes of thermoplastic protective sleevingaround different sizes of electrical elements to secure the sleeves thereto.

A device illustrating certain features of the invention for securing a protective thermoplastic sleeve to anelectrical element having leads extending. from opposite ends thereof may inclu'dea frame for supporting a stationary plate and a movable plated in an oblique position. The stationary plate and the platen have a plurality of slots extending inwardly from one edge thereof for receiving. the terminal. leads of'the resistor elements which are disposed between the. plate and the platen with the protective sleeves telescopedthereon; which sleeves are open at their upper ends and are supported on thestationary plate.

The platen is electrically heatedand has a' plurality of recessed cup-shaped forming surfaces engageable' with the upper ends of'the tube for heating and formingthem inwardly around the resistor'elements to secure the sleeves thereon as the platen is moved toward the plate by a fluid actuator and as the platen is retracted, a stationary member serves to engage the leads of the. resistor ele-. ment assemblies and push them free of the. platen inthe event the sleeves: adhere thereto; and an ejector member operable in response to the latter. portion of the retracting movement of the platen ejects the resistor element assemblies'fr'om the plate and the platen.

Other objects and advantages of the invention will become apparent by reference to the following detailed description thereof and the accompanying drawings, in which Fig. l is a sideelevational view of the resistor element with the protective sleeve partiallyassembled' thereon;

Fig. 2 is a view similar to Fig. 1' showing the protective sleeve secured to the resistorielement;

Fig; 3 is a side elevational view of the device for forming the open end' of the. sleeve around the resistor element;

Fig; 4 is a' face: view of the device shownin Fig. 3;.

Fig 5 is a diagram of the electrical control for the device;

Fig. 6 is a fragmentary plan sectional view taken on the line 66 of Fig. .4 showing the platen for forming the ends of the protector sleeves;

Fig. 7 is a. fragmentary vertical sectional view takenon the line 77 of Fig, 4;

Fig. 8 is a fragmentary plan view of. the stationary. plate for supporting the resistor. elements taken on the. line 88 of. Fig. 4; and

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Fig; 9' is. a fragmentary vertical sectional view taken on the .line..9-9 'of Fig. 7.

The presentdevice' is designed to secure a protectivethermoplastic sleeve20 onto cylindrical resistor elements 22 having metal end caps 23-24 and terminal leads 25 extending in opposite directions therefrom.

The sleeve 20- is in the form of a straight cylindrical tube with one end open or straight and the other end formed inwardly to-provide a rounded end 26 engageable with a cap 24 of the resistor element and forming an aperture 27 for receiving one of the leads 25. After the sleeve 20" is applied'to' the resistor element as shown in" Fig. 1, the upper open end of the sleeve is heated and formed inwardly to provide a curved end 28 engageable with the other cap 23 to secure the protective sleeve on the resistor'element and to form a central clearance aper ture 29 for the other lead 25 of the resistor element.

The device'compn'ses a C-shape'd frame supported on a bench ortable top 36 in an oblique position by means of an attaching bracket'or support 37. Mounted. on the lower portion. of the C-frame 35' is a. stationary supporti'ng plate or plates 39 of rectangular form with the forward portionithereof projecting outwardly beyond the frame for supporting the resistor elements 22 and sleeves 20 and having a plurality of slots 40 extending inwardly a predetermined distance from the forwardedge thereof for receiving the lower. leads 25. of the resistor elements 22'; The upper leads 25 of the resistor elements are adaptedtofit'into a plurality of slots 43 formed in theforward'edge of a movable platen 44in alignment. with the slots 40 in the plate 39. The movable platen is" carried'by a pistonv rod 45 of a fluid actuator 46 for reciprocable movement toward and away from the sup,- porting plate 39; The. arrangement of the plate 39 and the platen 44' is such that the resistor element 22, with. the. protective sleeve 20. thereon, may be positioned be.- tween the plate and the platen and supported on the former as shown in dotted lines in Fig. 3 with the lower and upper leads 25 fitting into and projecting through slots 40'and' 43; respectively.

The. platen 4'4 has a plurality of recesses 49 on the underneath side thereof providing cup-shaped forming surfaces engageable with the upper ends of the protective, sleeves 20' for forming the upper edge portions thereof inwardly to provide. the curved end walls 28 thereof. The recesses 49 have lower conical surfaces 50, which merge. with the curved portions 51 at the. upper portion thereof as shown in Fig, 9. The platen 44 is made from copper andInickelZ platedj and is heated to a temperatureof between250 and 325 for heating the upper ends. of the plastic sleeve to aid in forming. them around the.- resistor elements. The platen is. heated by a, pair of cartridge type heating, elements 53, which are inserted from opposite ends in a longitudinally disposed bore. 54 in'the platen. and are. connected to a suitable power line 55 (Fig. 5) through a pair of switches 56 of a thermostatic control unit 57 which is mounted on the frame 35;

and set. to the desired temperature by means of a control knob. 58. The control. unit 57 is operatively connected to. the platen 44 by. a heat responsive flexible capillary tube 60 which. has an enlarged tubular head 61 releasa-- bly supported. in engagement with the platen 44 by aspring clip 62.

A spacer 66 having arecess for receiving the flat spring clip 62, and a flange connector member 67 are secured to the platen 44 by a plurality of screws 68, and the flange. connector member 67 is threaded to the threaded shank of a connector. member 69 and locked thereto by a locknut 73. The connector. member 69 has a recessed end which is threaded andlocked to the piston rod 45 and forms an extension thereof. .The spacer 66 is made 3 from heat insulating material which serves to reduce the heat loss from the platen 44 to the support therefor. An arm 72 threadedly secured to the connector member 69 has a rod 74 fixed thereto which is slidable in an aperture 75 in the;frame 35 and serves to hold the platen 44 in proper alignment against angular displacementas it reciprocates.

The fluid actuator 46, which is secured to the upper end of the C-shaped frame 35, comprises a cylinder 48 in which a piston is reciprocable to which the piston rod 45 is secured. The fluid actuator 46 is connected to a compressed air line 79 .and is controlled through an electrical solenoid valve 80, which has a pair of solenoids 81 and 82 (Fig. for actuating the valve in opposite directions in response to alternate energization of the solenoids to efiect the raising and lowering of the platen 44. The solenoid 81 is connected to a normally open switch 83 which is momentarily moved to closed position by a foot actuated lever 84 to complete a circuit from a transformer 85 to energize the solenoid and effect the downward movement of the platen 44. An adjustable trip member 87 carried by the rod 74 (Fig. 3) is adapted to engage and close a switch 88 mounted on the frame 35 for closing a circuit from the transformer 85 to the solenoid 82 to energize the solenoid 82 and efiect the return movement of the platen 44 to its normal raised position, which is controlled by the engagement of a collar 90 with a stationary stop surface 91 (Fig. 7). The trip member 87 is in the form of a screw which may be adjusted to vary the stroke of the platen and the position at which it returns after completing the forming of the upper edges of the protective sleeves 20. A stop 92 in the form of an adjustable screw is mounted on the plate 39 in the path of the platen 44 to .arrest its downward movement in the event that the switch 88 and the control circuit fails to stop the downward movement of the platen at a predetermined position. The foot lever 84 may be moved in the reverse direction to close a switch 93 to effect the energization of the solenoid 82 and the return movement of the platen 44 in the event of failure of the switch 88.

In the operation of the device, the resistor elements, with the sleeves 20 telescoped thereon, are placed on the supporting plate 39 in the position shown in dotted lines in Fig. 3 and the foot pedal 84 is rocked forwardly to momentarily close the switch 83 and effect the downward movement of the heated platen 44 and the engagement of the upper ends of the sleeves 20 with the forming recesses 49 to effect the forming of the upper portions of the sleeves into rounded ends 28. During the forming operation, a portion of the upper ends of the sleeves 20 are disposed in the slots 43 and will not be formed into the curved shape shown in Figs. 2 and 9 so that a slight irregularity or projection 95 (Fig. 7) will be formed on the upper end portion 28 of the sleeve 20. Because of this and the plasticity of the sleeve 20, the sleeve in some instances tends to adhere to the platen as the platen is withdrawn to its upper or retracted position.

In order to releaseand separate the resistor assemblies that might adhere to the heated platen 44 as it is moved supported in position to receive them.

The platen 44 along the rear longitudinal edge thereof is provided with a plurality of slots 143 and a plurality of forming recesses 149 on the underside thereof correspond-ing to the slots 43 and the recesses 49 but with i the forming recesses 149 of a larger size than the reto its retracted position, a stationary knockout plate 96 is mounted in the path of movement of the upper leads 25 of the resistor assemblies for arresting the upward movement thereof prior to the arrival of the platen 44 to its upper position. The knockout plate 96, as shown herein, is mounted on the lower ends of a pair of supporting rods 97, which are adjustably secured by screws 98 in the upper end of the frame 35.

On completion of the forming operation, the row of resistor assemblies are ejected by an ejecting member cesses 49 for forming the upper edge portions of protective sleeves inwardly around the ends of the resistor units of a larger size in the same manner as described heretofore. When it is desired to use the device on the resistor element assemblies of a larger size, the heating elements 54 and the heat-responsive element 61 are removed from the platen 44 and the platen rotated 180 to position the slots 143 and the cup-shaped forming recesses 149 above and in alignment with the slots 40 on the supporting plates 39. The heating elements 54 and the heatresponsive elements 61 are then replaced in the platen 44, as shown in Fig. 3, and the adjustable collar 90 and the adjustable trip 87 readjusted to effect the proper stroke of the platen consistent with the larger size of resistor element assemblies to be worked upon.

It is to be understood that the above-described arrangements are simply illustrative of the application of the principles of this invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. In a device for forming the ends of protective thermoplastic sleeves around the ends of electrical elements to form electrical components in which the elements have straight Wire leads extending from opposite ends thereof and beyond the ends of the sleeves, the combination of a stationary platen, a movable platen, a frame for supporting the stationary platen in an oblique position, means on the frame for moving said movable platen toward and away from the stationary platen in an oblique direction, said platens having a plurality of aligned slots for locating and supporting the wire leads of the components along predetermined axes parallel to the said oblique direction and for lateral movement of the leads into and out of the slots, the movable platen having forming recesses aligned with the end of the slots therein and the said axes for forming the ends of the sleeves around the electrical elements, means for heating the movable platen, and stationary means engageable with the leads on one end of said electrical components for arresting the movement thereof with said movable platen to effect the release of the components from the movable platen when they adhere thereto.

' aligned slots for locating and supporting the wire leads 101 in the form of a bar, which is supported at its ends by a pair of arms 102, the upper ends 103 of which are bent inwardly and pivotally supported in apertures in of the components along predetermined axes disposed parallel to said oblique direction and for lateral movement of the leads into and out of the slots, the movable platen having forming recesses aligned with the ends 'of the slots therein and the said axes for forming the ends of the sleeves around the electrical elements, means for heating the movable platen, stationary means engageable with the leads on one end of said electrical components for arresting the movement thereof with the movable platen to efiect the release of the components from the platen when they adhere thereto, an ejector element pivotally supported on the frame and gravity actuated in one direction to a normal position between the platens and adjacent the electrical components, and a member on said piston operable in response to movement of the movable platen from the stationary platen for actuating the ejector element to eject the components.

3. In a device for forming the end of a protective thermoplastic sleeve around the end of an electrical element to form an electrical component in which the element has straight wire leads extending from opposite end-s thereof and beyond the ends of the sleeve, the combination of a stationary platen, a movable platen, a frame for supporting the stationary platen in an oblique position, means on the frame for moving said movable platen toward and away from the stationary platen in an oblique direction, each of said platens having a slot aligned with each other for receiving the wire leads of the component therein and for supporting them along an axis parallel to said oblique direction, the movable platen having a forming recess aligned with the end of the slot therein and said axis for forming the end of the sleeve around the electrical element, means for heating the movable platen, stationary means engageable with the lead on one end of said electrical component for arresting the movement thereof withsaid movable platen to release the components from the movable platen if it should adhere thereto, and means operable in timed relation to the movable platen for ejecting the component.

References Cited in the file of this patent UNITED STATES PATENTS 1,273,009 Simmons July 16, 1918 1,302,722 Sokolow et al. May 6, 1919 1,826,505 Conn Oct. 6, 1931 2,104,166 Pelton Ian. 4, 1938 2,169,315 Yngve Aug. 15, 1939 2,259,508 Abramson Oct. 21, 1941 2,271,774 Megow Feb. 3, 1942 2,273,190 Harrison Feb. 17, 1942 2,293,287 Franz Aug. 18, 1942 2,492,483 Keene Dec. 27, 1949 2,637,144 Gardner et al. May 5, 1953 

